Aspirin guidelines need overhaul, researchers say

NEW YORK (Reuters Health) - Healthy people shouldn't be taking aspirin to prevent heart disease, researchers say in a new report that casts doubt on recommendations from U.S. health officials.

Medical guidelines currently urge people to take low doses of the drug if they are at high risk of heart disease but have never had any symptoms, or if they have already suffered a heart attack.

But the first piece of advice, known as primary prevention, has come under attack from more and more doctors because aspirin therapy can also be harmful.

"What we need to focus on is lifestyle, smoking cessation, and statin and blood pressure medications," said Dr. Kausik Ray, who studies heart disease prevention at St. George's University of London and led the new work. "I don't recommend aspirin."

Ray and his colleagues took a fresh look at nine previous trials of aspirin use in people who had never had chest pain or other symptoms of an ailing heart. They also looked for signs that the medication might stave off cancer, which some research has suggested.

Based on more than 100,000 men and women followed for an average of six years, there was no sign aspirin prevented fatal heart attacks. But it did cause a tiny drop in non-fatal heart attacks.

Among people taking placebo pills without active ingredients, 1.7 percent had a heart attack and survived, compared to 1.3 percent of people on aspirin.

That means 162 people would have to be treated for six years to avert just one non-fatal heart attack, the researchers write in the Archives of Internal Medicine.

There was no difference in fatal heart attacks or cancer deaths, and overall death rates were 3.8 percent in both groups. However, there was a clear harm from taking the drug, which can be bought for pennies at any pharmacy.

"The flipside is, there is a 30-percent increased risk of bleeding and these are not trivial bleeds," Ray told Reuters Health.

The rate of serious bleeding -- say, from a stomach ulcer -- was 10.1 percent among people on aspirin and 9.6 percent in the placebo group.

'A NET HARM'

Even among people at high baseline risk, Ray said, "there is never a net benefit."

For every two cases of heart disease and stroke prevented by aspirin, there were more than three cases of serious bleeding.

"It is actually not net benefit, it is a net harm," Ray said, adding that the findings were the same for men and women.

Other teams of scientists have recently analyzed the same data Ray looked at, and one interpreted the results in favor of aspirin.

Currently, U.S. guidelines all recommend aspirin for primary prevention as long as the benefits outweigh the harms, an equation that depends on baseline risk. This advice is backed by an editorial accompanying the new report.

However, even for people at high risk, not all researchers think aspirin is worth it.

In November, for instance, Dutch researchers reported that 50 women at high risk for heart disease would need to take aspirin for 10 years to see a net benefit for one.

Based on the latest findings, Ray's team concludes, "it is perhaps timely to reappraise existing guidelines for aspirin use in primary prevention."